My empisal knitting machine has a red release button, but it is jammed ?

If my machine gets stuck there is a red release button which should allow me to lift the the handle then let me knit
accross the garment to then untangle the wool. But this red button
to the right just at the side of the handle is jammed fast.
Otherwise the machine works, but when in trouble I have to undo everything to get the tangles out, which ruins the garment I am knitting.